[A smoking, coughing young adult].

A 30-year old man who smoked, presented with cough, dyspnoea and fatigue. Radiography showed diffuse bilateral symmetrical nodules, partially cavitating. The histopathological findings from the thoracoscopic wedge resection were specific for pulmonary Langerhans cell histiocytosis. The patient immediately quit smoking, which resulted in less complaints and decreased abnormalities on the x-ray.